I think everyone is different and one night out off diet will affect everyone diiferently, some will gain and some will not be affected.

I have been dieting 3 months now and I am now noticing a pattern.

If I mess up (hit a buffet, or eat to much at a party or something like that) once during the week and stay on track the rest of the week I can usually still lose a pound or two. If I mess up twice during the week I will not gain or lose and mess up 3 times I gain.

When I first started I lost weight 8 weeks in a row averaging 2-6lbs a week with an average of 3 lbs. On the 9th week I gained 1.6 lbs. I was so upset for slipping (I pigged out at a truckstop buffet, Super Bowl Party and ate junk driving on a long trip) I just didn't want to get back on track and forget about it. I felt a need to lose not only the pounds I would have for that week but lose the pounds I WOULD have lost for the week before!

The following week for 3 of the 7 days I did double aerobics (TWO hours on the elliptical, one in the morning and one at night) and I ate super clean and very low calorie (under 1200 calories) and at my next Weight Watcher's weigh in I lost 6.6 pounds!

I felt like I redeemed myself! LOL! It was a tough week but I made it and then went back to my regular routine of 1 hour per day elliptical machine and 1800 calories per day.